Disabling current from signal?

Thread Starter

x03n

Joined Nov 30, 2020
8
Hi I'm relatively new to circuits and am trying to run LED lights on my motorcycle. Im running into a problem I cant figure out.

I plan on running in series a switch to the LEDs so they can be always ON until I flip on the turn signal. For example if I turn on my left turn signal, the right LEDs stay constant, but the left LEDs flash at the same time as the blinkers.
I can't seem to get that 'inverse curve' on my current draw and cancel out the LEDs, disabling them for the allotted time the flasher is on. I have multiple circuit designs in attempt to create this but 1.jpg is what I want, just without 5 relays. The 3 switches on top are ON/OFF, Left Turn Signal, Right Turn Signal. I did wire up 2.jpg and it worked however within a minute the transistors got too hot and burnt out from constant high amperage draw.

How can I disable the current to the LEDs using the signal from the blinker lights? Thanks in advance

1.jpg:
1.png

2.jpg:
2.png
 

Thread Starter

x03n

Joined Nov 30, 2020
8
Here is a link to the LED strip that I am using but don't know if AAC will remove it: https://www.amazon.com/300Leds-Waterproof-Flexible-Outdoor-Decoration/dp/B01HPTLW2S

It looks like there is some little modules (maybe diodes?) between the LEDs but cant determine what they are. Where would I put the resistors while still allowing the lights full brightness?

When powering the lights they pull 500mA. It is an Automotive battery running 12v. I haven't measured blinker output
 

crutschow

Joined Mar 14, 2008
27,170
When powering the lights they pull 500mA.
Okay, then they have built-in current limiting and don't need any added resistors.

I don't really understand your circuit 2 and how the transistors are supposed to do what you want.

What part number are the transistors?
 

Thread Starter

x03n

Joined Nov 30, 2020
8
If I'm completely honest: That's me reaching for straws hoping something turns up in simulation
The 5 relays was overkill so in return I learned transistors just to simplify the circuit, It did show up good in the sim but the sim does not account for heat dissipation
If you have specifics on what I need to read then I'll do that and make adjustments accordingly
Diodes: IN5408
Transistors: S9014

Edit: When the LTS is on (2.jpg) it runs a pulse to the diode and flashes the LEDs directly. If the switch is on for LEDs (middle), then its ran in parallel for the transistor to send signal through both the diode and transistor to pulse while still illuminating.
 
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Thread Starter

x03n

Joined Nov 30, 2020
8
This table kind of explains what I am trying to accomplish here:

Main: OFF
LTS: OFF
LLED: OFF
RLED: OFF

Main: ON
LTS: OFF
LLED: ON
RLED: ON

Main: ON
LTS: ON
LLED: FLASH WITH BLINKER, 0% to 100%
RLED: ON

Main: OFF
LTS: ON
LLED: OFF
RLED: OFF

The third set is where I am having issues. Circuit 2 did work for a short time, but instead went from 50% to 100%
 

eetech00

Joined Jun 8, 2013
2,349
Here is a link to the LED strip that I am using but don't know if AAC will remove it: https://www.amazon.com/300Leds-Waterproof-Flexible-Outdoor-Decoration/dp/B01HPTLW2S

It looks like there is some little modules (maybe diodes?) between the LEDs but cant determine what they are. Where would I put the resistors while still allowing the lights full brightness?

When powering the lights they pull 500mA. It is an Automotive battery running 12v. I haven't measured blinker output
So...how many LEDs are you going to use for each blinker strip?
 

Thread Starter

x03n

Joined Nov 30, 2020
8
It varies by length, I've made an Excel sheet to demonstrate:

Few things on the image:
1. 'Flash?' means it will be ran to blink at the same rate as the blinker, a couple centered pieces should not flash at all
2. 'F. Req'd' means I require my fairings to complete the install; F. is in the shop being hydro dipped and I cannot install these yet.
3. #29 is mounted on the bottom of the rear swing arm, just behind #16a.

Running all installed pieces directly to battery they have full brightness, everything is in working order. Just need to figure out the engineering aspect of it to make them flash, which I'm not sure how to do that

Edit: The BlueGreenBrownOrange is my key to determine where the lights that I am installing are from. I'm using Cat5 cable. E.g. A Blue wire shouldn't be wired to the right turn signal
 

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eetech00

Joined Jun 8, 2013
2,349
It varies by length, I've made an Excel sheet to demonstrate:

Few things on the image:
1. 'Flash?' means it will be ran to blink at the same rate as the blinker, a couple centered pieces should not flash at all
2. 'F. Req'd' means I require my fairings to complete the install; F. is in the shop being hydro dipped and I cannot install these yet.
3. #29 is mounted on the bottom of the rear swing arm, just behind #16a.

Running all installed pieces directly to battery they have full brightness, everything is in working order. Just need to figure out the engineering aspect of it to make them flash, which I'm not sure how to do that

Edit: The BlueGreenBrownOrange is my key to determine where the lights that I am installing are from. I'm using Cat5 cable. E.g. A Blue wire shouldn't be wired to the right turn signal
So...how many LEDs are you going to use for each blinker strip?

This is important to know so we know the load currents we need to deal with....
 

Thread Starter

x03n

Joined Nov 30, 2020
8
If by blinker strip you mean how many will be ran in total:
Total Right side Flashing LEDs: 51
Total Left side Flashing LEDs: 51
Total Non Flashing LEDs: 57
 

djsfantasi

Joined Apr 11, 2010
7,689
What is the output of the flasher when not activated? If it’s floating, then start by adding a pull up resistor to the output. If it’s low, then use an NPN as an inverter. Both cases result in a high output when not being used.

Feed this output into an AND gate built using transistors. And connect this output in parallel to a discrete component OR gate. This OR gate output connects to the second AND gate input. The remaining OR gate input connects to the headlight ”On” switch, with a pull down resistor.
 

Thread Starter

x03n

Joined Nov 30, 2020
8
Wow, djsfantasi that was overwhelming at first. I didn't know what 75% of that was so I researched it all and came up with an Inverter is probably my best bet.
I tried following your instructions to a tee but was unsuccessful, it works but it still is just overlapping amperage instead of actually going 0% to 100%. It is going 50% to 100% still like my first transistor circuit. I trust you know what it requires to complete it correctly maybe I just designed it incorrectly. These are the designs I came up with:

A is my attempt at following your instructions
B is the inverter circuit, it fully worked in simulation, but in real life the (S9014) transistor caught on fire for some reason, swapping for another, it worked fine just didn't flash with the blinker at all
 

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dendad

Joined Feb 20, 2016
3,835
How about just wiring the LED strips from +12V to the hot end of the existing flasher lamps, assuming they are lamps and not more LEDs.
The LEDs may not draw enough current to operate filament lamps, so the LEDs will be on and the lamps appear off.
Then, when the flasher operates, the LEDs will be shorted out and stop while the lamps light. The sense will be inverted but still indicate the flashing.
 
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djsfantasi

Joined Apr 11, 2010
7,689
Wow, djsfantasi that was overwhelming at first. I didn't know what 75% of that was so I researched it all and came up with an Inverter is probably my best bet.
I tried following your instructions to a tee but was unsuccessful, it works but it still is just overlapping amperage instead of actually going 0% to 100%. It is going 50% to 100% still like my first transistor circuit. I trust you know what it requires to complete it correctly maybe I just designed it incorrectly. These are the designs I came up with:

A is my attempt at following your instructions
B is the inverter circuit, it fully worked in simulation, but in real life the (S9014) transistor caught on fire for some reason, swapping for another, it worked fine just didn't flash with the blinker at all
I may have misused the term “inverter”. I am referring to a circuit that takes a high level and outputs a low level. Also, it takes a low and outputs a high.

Post your schematic.
 

Thread Starter

x03n

Joined Nov 30, 2020
8
wiring the LED strips from +12V to the hot end of the existing flasher lamps
Doing this does flash the LEDs, but when I off the turn signal the LEDs also stay off. If I used a diode to add the turn signal with underglow, it would also make it mid brightness (50%) to full brightness (100%) again. Unless I am not interpreting what you mean correctly?

Post your schematic.
I did attach 2 files and mentioned what they were but I'm not sure if only I can see them? I'll reattach them again.
A.png
B is the inverter circuit, it fully worked in simulation, but in real life the (S9014) transistor caught on fire for some reason, swapping for another, it worked fine just didn't flash with the blinker at all
B.png

As for the turn signals I was using an LED/Brake light combination, but late March of this year I was ran over by a guy with no license, insurance or tags. I've taken it onto myself during my COVID layoff to rebuild the bike and figured I'd make the lights completely overkill so I can stop getting ran over. They say loud pipes save lives but it was night time on a 65mph highway, so now its Bright Lights Save Lives. It wasn't until after receiving the new tail light that it didn't have turn signals in it, so I made 2 12" strips of red ran to turn signal circuits.
 
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